Weft detector mechanism



1962 H. A. BATTY ETAI. 3,049,152

WEFT DETECTOR MECHANISM Filed March 22, 1960 3,49,152 Patented Aug. 14, 1962 i. tittes WEFT DETECTOR MECHANISM Harry A. Batty, Lexington, Arthur .I. Eisler, Glasgow, and John W. Ellington, Greenlee, Va., assignors to James Lees and Sons Company, Bridgeport, Pa, a corporation of Pennsylvania Filed Mar. 22, 1960, Ser. No. 16,780 1 Claim. (Cl. 139-370) This invention relates to stop motions and more particularly to a missing or slack weft detector for a pile fabric shuttle loom.

In order to improve the eificient operation of pile fabric looms such as Wilton and velvet carpet looms it is desirable to insure that the loom stops at once in the event there is a filling break or the filling weft becomes exhausted. The present invention pertains to a simple automatically timed sensing element which detects the absence of a filling weft at a predetermined time in the weaving cycle and in the event no weft is in fact present, suitable electrical circuits are triggered to stop the loom.

A primary object of the invention, therefore, is to provide an improved filling stop motion for a broad carpet loom.

A further object of the invention is to provide a weft detecting finger which is pivoted to a detecting position beside the shed at approximately the same time the loom reed heats up.

Further objects will be apparent from the specification and drawings in which:

FIG. 1 is a fragmentary section in detail showing the present invention applied to a pile fabric loom,

FIG. 2 is a top view of the structure seen in FIG. 1 also showing part of the shuttle box,

FIG. 3 is a fragmentary detail of the detecting finger of FIG. 1 in a moved position,

FIG. 4 is a perspective of the structure of FIG. 3, and

FIG. 5 is a wiring diagram showing the stop motion supports.

Referring now more particularly to the drawings, a conventional Wilton or velvet loom is equipped with oscillating lay which carries the usual reed 11 and shuttle box 13. The shuttle 14 is projected back and forth across the lay and in front of the reed to carry filling wefts 15 back and forth through the shed S of the pile warps in accordance with standard practice. The shuttle 14 carries a cop 16 of filling yarn which is trained through the eye 17 of the shuttle. The movable shuttle swell 18 serves to hold and release the shuttle 14 in the shuttle box in accordance with the actuation of the picking motion, all of which is conventional. The reed 11 not only beats up filling wefts 15 into the fell 20 of the fabric F but also simultaneously beats up a series of pile wires 21, 21 which are inserted into the upper pile shed by means of the usual Wire motion. A series of such pile wires 20, 20 is shown in FIG. 2.

The present invention comprises a weft detector finger 25 which is pivotally mounted on a rocker arm 26 at post 27. Rocker arm 26 is in turn pivoted at 28 on a bracket 29 secured to any fixed part of the loom frame 30. Oscillation of arm 26 on bracket 29' is controlled by means of a cam 31 secured to the loom camshaft 32 and positioned to pivot a walking beam 33 through cam follower 34. Walking beam 33 is pivoted to the loom frame .at 35 and is biased by means of a tension spring 36. An adjustable rod 37 pivoted to arm 26 at 38 and to walking beam 33 at 39 transmits oscillating motion of the walking beam to arm 26 and serves to dip the weft detecting finger 25 to a downward position in front of the filling shot at a timed position of the weaving cycle.

With the lay 10 and reed 11 on the back-center position as shown in FIG. 1 the shuttle 14 is thrown and a pile wire 21 inserted either on every pick or in any other relationship with the number of filling wefts depending upon whether a one, two, or three shot fabric is being woven. As the reed 11 heats up, cam 31 turns to lower Weft detecting finger 25 to the position shown in FIG. 3 so that the finger is in front of the filling weft 15 that has just been inserted. Continued beating up of reed 11 causes the filling 15 to pivot finger 25 on post 27 against the pressure of compression spring 45. If no filling 15 is present at this particular point in the cycle due to either a broken or exhausted weft, no pivoting action of the finger takes place and the switch actuator 46 remains positioned against the stop pin 47 thereby failing to open normally closed switch 48.

Referring now to FIG. 5, the main loom switch Si) is connected across the power lines 51 and 52 through the main motor relay 53. A holding circuit for the armature 54 of relay 53 is completed through the normally closed contacts 55 and 56 of holding relay 57. A cam actuated switch 58 is normally open except When the lobe 59 of cam 6t) contacts cam follower 61 to close switch 58 at the point in the cycle that arm 26 is dipped. Relay 57, however, is not energized to open contacts 55 and 56 unless switch 48, normally closed, fails to open by pivoting of finger 25 and actuator 45. The absence of a filling weft at the time switch 58 is closed to condition the circuit to relay 57 means that switch 48 remains closed thus energizing relay 57, breaking the hold circuit to relay 53 and stopping the main loom motor 60 by opening the contacts of relay 53. Uninterrupted operation of the loom simply causes normally closed switch 48 to be held open by the filling Weft when switch 58 is closed by cam 60.

The device described above is a simple, efiicient weft detector for a broad pile carpet loom. The sensing or detecting element operates in timed relation with the beat-up of the reed so that the absence of a filling shot or a completely slack shot is detected in the loom stop before the reed fully beats up. In addition, the actual detecting movement is originated by means of the reed during beat-up so that it is only necessary to properly position the sensing element in front of the filling at the proper time in the cycle. This eliminates the necessity for complicated detecting mechanism.

Having thus described our invention, We claim:

In a transverse wire pile fabric loom, having a plurality of pile wires successively inserted into warp sheds, an oscillating lay, a shuttle on said lay for throwing weft shots transversely through said sheds, a reed on the lay for beating up the pile wires and the weft shots against the fell of the fabric being woven, a rocker arm pivotally mounted at a position spaced transversely at one side of the sheds, a weft detecting finger pivotally mounted on said rocker arm, means for moving the rocker arm in timed relation to the operation of the lay to dip the detecting finger to a position spaced transversely beyond one side of the sheds and between a normal filling shot and the line of the fell extended transversely beyond one selvedge, a switch mounted on the rocker arm having an actuator operatively associated with the finger, and means connected with said switch for stopping the loom in the event the finger is not displaced by a normal filling shot substantially before the reed beats up against the fell.

References Cited in the file of this patent UNITED STATES PATENTS 2,600,667 Mason June 17, 1952 2,646,827 Cederlund July 28, 1953 2,819,737 Opletal Jan. 14, 1958 

